Cress Tool Suite
Cress is a comprehensive toolset for graphical service/workflow design
... and validation.
Cress aims to make service design as easy as possible without requiring specialist development knowledge. It simplifies service creation to drawing diagrams, clicking buttons and defining a few tool parameters. All key functions of Cress can be controlled from the Chive diagram editor.
Cress is written using portable and widely used languages (Perl and Java). It can be extended by a developer for other kinds of services that can be characterised by activity flows.